Windows Development in C++, COM API Clients

#include "stdafx.h"

#include "hnum_pzsp_defs.h"

namespace harlinn
{
    namespace numerics
    {
        namespace SuperLU
        {
            double dzsum1_(int *n, doublecomplex *cx, int *incx)
            {
            /*  -- LAPACK auxiliary routine (version 2.0) --   
                    Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,   
                    Courant Institute, Argonne National Lab, and Rice University   
                    October 31, 1992   

                Purpose   
                =======   

                DZSUM1 takes the sum of the absolute values of a complex   
                vector and returns a double precision result.   

                Based on DZASUM from the Level 1 BLAS.   
                The change is to use the 'genuine' absolute value.   

                Contributed by Nick Higham for use with ZLACON.   

                Arguments   
                =========   

                N       (input) INT   
                        The number of elements in the vector CX.   

                CX      (input) COMPLEX*16 array, dimension (N)   
                        The vector whose elements will be summed.   

                INCX    (input) INT   
                        The spacing between successive values of CX.  INCX > 0.   

                ===================================================================== 
            */  

                /* Builtin functions */
                double z_abs(doublecomplex *);
    
                /* Local variables */
                int i, nincx;
                double stemp;


            #define CX(I) cx[(I)-1]

                stemp = 0.;
                if (*n <= 0) {
	            return stemp;
                }
                if (*incx == 1) {
	            goto L20;
                }

                /*     CODE FOR INCREMENT NOT EQUAL TO 1 */

                nincx = *n * *incx;
                for (i = 1; *incx < 0 ? i >= nincx : i <= nincx; i += *incx) {

	            /*        NEXT LINE MODIFIED. */

	            stemp += z_abs(&CX(i));
            /* L10: */
                }
    
                return stemp;

                /*     CODE FOR INCREMENT EQUAL TO 1 */

            L20:
                for (i = 1; i <= *n; ++i) {

	            /*        NEXT LINE MODIFIED. */

	            stemp += z_abs(&CX(i));
            /* L30: */
                }
    
                return stemp;

                /*     End of DZSUM1 */

            } /* dzsum1_ */

        };
    };
};